Cisco Nexus 2000 Series
Cisco Nexus 2000 series are fabric extenders (FEX): 'top of rack' 1U high system that can be used in combination with higher end Nexus switches like the 5000, 6000 or 7000 series: the 2000 series is not a 'stand-alone' switch but needs to be connected to a parent and should be seen as a 'module' or 'remote line card' but then installed in a 19" rack instead of in a main switch-enclosure. The interconnection between this 'remote line card' and the 5000 or 7000 parent switch uses either proprietary interfaces (CX-1 for copper or the short or long range Cisco Fabric Extender Tranceiver (FET) interfaces), or standard interfaces (Cisco SFP+ SR and LR fibre interface modules or SFP+ Twinax cables). In combination with the 5000/6000/7000 mother-switch you can create a so-called Distributed Modular System.
Cisco Nexus 2000 series consists of 4 different models. Three models offer 24 or 48 gigabit only or gigabit/fastethernet copper interfaces and up to 4 10 Gigabit uplink interfaces on copper or fibre. The Nexus 2232PP offers thirty-two 1/10 Gbit/s ethernet and FCoE interfaces. The Nexus 2248PQ offers forty-eight 1/10 Gigabit ethernet and FCoE interfaces.